The program has as its objective the discovery of the nature of the neuromotor systems underlying speech production. We are concerned with the nature of facial muscle function as it related to skilled motor activity involved in both speech and non-speech movements. Specifically, we are investigating these functions in normal human subjects, neurologically disordered human subjects, normal non-human primates and neurologically altered non-human primates. Data from parallel studies of human and animal subjects will be used to provide our quantitative model with information that can permit the use of the predictive capacities of the model. We are employing a multidisciplinary approach; the unifying system science context provides the framework for our individual research activities. The ultimate goal, of course, is an accurate description and a clearer understanding of the strategies and mechanisms underlying speech motor control.